A 71-year-old Sikh man was violently assaulted in Northern California during

A 71-year-old Sikh man was violently assaulted in Northern California during his morning walk on Monday ― and a police chief later identified his own estranged son as one of the perpetrators.

Union City Police Chief Darryl McAllister penned a heart-wrenching open letter to his community on Wednesday, saying he was “disgusted” to share that his 18-year-old son, Tyrone Keith McAllister, is a suspect in the crime.

“Words can barely describe how embarrassed, dejected, and hurt my wife, daughters, and I feel right now,” McAllister wrote in a letter posted on Facebook.

“Violence and hatred is not what we have taught our children; intolerance for others is not even in our vocabulary, let alone our values. Crime has never been an element of our household, our values, nor the character to which we hold ourselves.”

Footage of the attack, caught on a nearby security camera, shows Sahbit Singh Natt walking along Greystone Park in Manteca, California, when two individuals confront him. One of them, suspected of being McAllister’s son, can be seen kicking Natt to the ground and then kicking him repeatedly.

According to McAllister, Natt suffered “minor physical injuries.”

Police said the incident was a suspected robbery, but the San Francisco Chronicle reported that detectives are also trying to determine if the attack was motivated by hate. Manteca is located about 60 miles east of Union City.

Dr. Rajwant Singh, co-founder of National Sikh Campaign, said he was “appalled” and “disturbed” by the recent attacks on Sikh Americans. A 50-year-old Sikh man was brutally attacked in California last week. That incident is being investigated as a hate crime.

McAllister described how he and his wife helped Manteca authorities track down his son and arrest him on Wednesday.

“Despite having the desire any parent would have in wanting to protect their child, my oath is (and always will be) to the law and my vow of integrity guides me through this horrendous difficulty,” McAllister wrote. He shared details of his son’s journey over the past few years, which involved running away, associating with a “bad crowd,” participating in theft-related crimes, serving a stint in juvenile hall and another 3-month sentence in adult jail. McAllister says his son has not returned home in several months.

“It’s difficult for us to comprehend how one of three kids who grew up with the same parents, under the same roof, with the same rules and same values and character could wander so far astray,” McAllister wrote.

Within a few hours of the chief’s posting, the letter received overwhelmingly positive feedback from commenters for its honesty.

Read the letter in its entirety below.

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